The storage of plutonium and nuclear toxic waste is becoming evermore a problem. A problem with plutonium and other nuclear waste is the need to store such waste for a very long time in view of the relatively long half-life of such material. For example, some nuclear waste material have a halfolife that is more than 100 years. Substantial exposure to nuclear material can be a health hazard and, in fact, can be fatal.
One technique for storing plutonium and other nuclear waste has been to place the waste in a container and to bury the container. (Hereinbelow, reference to nuclear waste includes plutonium as well as other nuclear materials, especially those which emit nuclear radiation.) A disadvantage to this technique is the possibility that the container can rust or otherwise corrode, and the nuclear waste can leak. For example, if the nuclear waste were to leak into the ground, it could contaminate the ground water and eventually cause harm to animals, fish, vegetable life, and possibly to humans. Another disadvantage is that the radiation from the nuclear waste can too easily be emitted into the external environment causing a health hazard, for example.
One technique for shielding nuclear waste has been to provide several inches, for example, at least three inches of lead shielding, to surround the nuclear waste. Such lead shielding tends to prevent the transmission of radiation to the external environment. Another technique has been to use at least three feet of water placed between the nuclear waste and the external environment to prevent transmission of radiation to the external environment.
Storage of non-radioactive toxic waste also presents problems similar to those encountered with the storage of toxic nuclear waste. For example, if the toxic waste were placed in drums and buried, leakage due to rusting or corrosion can cause contamination of drinking water and other waters used by fish, animals and plant life.
A difficulty encountered when storing toxic waste, whether nuclear or non-radioactive, is the heat often generated during storage. Excessive heat can trigger undesirable reactions, including the possibility of explosive activity. This, of course, is undesirable, as it tends to result in a release of the toxic waste to the external environment.
One reason that nuclear waste has been buried in the ground in the past has been the good shielding provided by the ground. Also, prior above ground shelters considered for storing nuclear and other toxic waste contemplate or use concrete and metal wall and roofs; the heavy weight of the roof makes design and construction difficult and sturdiness of the structure questionable. If such structures are used, of necessity they must be small. Today there is no way permanently or substantially permanently to store large quantities of plutonium. Since 1988 over $20 billion has been spent by the U.S. Department of Energy for disposing of nuclear waste; but there has been no improvement in methods and techniques according the Secretary of the Department of Energy. However, when using the ground for shielding, a problem is encountered in the case of a spillage, leak, etc. of the primary containment medium, such as a metal drum or the like.
Encasement using STAYTEX.RTM. material can be used for asbestos, lead, etc. for disposal in ordinary landfills. An example of such encasement is described in commonly owned pending U.S. patent application Ser. No. 08/064,548 filed May 19, 1993.
With the foregoing in mind, it will be appreciated that improvements in storage of toxic waste, both of the nuclear type and the non-radioactive type are desired.